1. Field of the Invention
The present invention relates to an image forming apparatus, a sheet containing device, a sheet inserting device, a book-binding system, and a sheet processing apparatus. In particular, the present invention relates to an image forming apparatus, a sheet containing device, a sheet inserting device, a book-binding system, and a sheet processing apparatus, which can be suitably used for the purpose of laborsaving or the like in an image forming system in which a plurality of image forming apparatuses are connected to a network.
2. Description of the Related Art
Conventionally, when printing out a plurality of types of originals consisting of color originals and black-and-white originals in a system in which a color image forming apparatus (color copying apparatus) capable of forming color and black-and-white images and a black-and-white image forming apparatus (black-and-white copying apparatus) capable of forming only black-and-white images are connected to a network, the user uses the color image forming apparatus (color copying apparatus) to print out all of the plurality of types of originals to obtain a printed matter composed of color pages and black-and-white pages.
On the other hand, since the color copying apparatus requires higher cost and time for image formation as compared with the black-and-white copying apparatus, the black-and-white copying apparatus has been required to be used to print out black-and-white originals among a plurality of types of originals consisting of color originals and black-and-white originals. Accordingly, it may be considered that, when printing out a plurality of types of originals consisting of color originals and black-and-white originals, the black-and-white copying apparatus is used to print out the black-and-white originals and the color copying apparatus is used to print out the color originals.
In this case, to collect recording sheets printed out by the black-and-white copying apparatus and recording sheets printed out by the color copying apparatus into one unit like the original plurality of types of originals consisting of the color originals and the black-and-white originals, the user needs to insert (interleave) the recording sheets outputted by one copying apparatus between the recording sheets outputted by the other copying apparatus and then manually arrange the recording sheets in page order.
As described above, when printouts from a plurality of images are desired to be arranged into one document, a part of the printouts cannot be processed on a computer. Thus, the user must manually work on the printed-out images spread out on a desk, which is very inefficient. From this standpoint, laborsaving is desired (the first prior art).
For the purpose of laborsaving, a method has been proposed in which one tray (hereinafter referred to as “the stacker tray”) is commonly used as a stacker tray (containing means) used for temporarily containing color image output sheets outputted by a color MFP (multifunction peripheral equipment) and as an insert tray (reefed means) used for inserting color image output sheets between black-and-white image output sheets in a black-and-white MFP to collect the color image output sheets and the black-and-white image output sheets into one unit in which these output sheets are mixed together. In this method, color image output sheets outputted by the color MFP, whose output speed is lower than that of the black-and-white MFP, are stacked and stored in the stacker tray, and the stacker tray is attached to an inserting device (inserter) of the black-and-white MFP to refeed the color image output sheets, so that the color image output sheets and the black-and-white image output sheets can be mixed (the second prior art)
On the other hand, the “on-demand printing” field has drawn more attention in the field of digital copying and printing. The on-demand printing can satisfy the need for high-mix small-lot printing, and allows modifications of contents. Thus, the on-demand printing is suitable for producing documents such as manuals, brochures for personals, and so forth. Further, the one-demand printing considerably reduces the man-hour and time by greatly reducing the print inventory and enabling in-line operation from the input of data to completion of book-binding, and considerably reduces the delivery time and cost by making it easier to transfer data due to connection with terminals of clients via a digital network.
In recent years, image recording apparatuses such as digital copying machines based on the above described on-demand printing technique have been widely used, and the image qualities thereof have been improved to the level of printed matters. Further, due to the recent rapid spread of personal computers (PC) for offices and personals, a plurality of client apparatuses such as PCs can be connected to a plurality of image recording apparatuses such as digital copying machines equipped with print servers via in-house office local area networks (LAN) or digital networks to construct a network system so that necessary image information can be freely recorded on sheets at any given time.
As a post-processing apparatus for use in combination with the above-mentioned networked image recording system to produce only a small amount of booklets such as catalogs, manuals, circulars at offices, or the like, a collating and binding apparatus is known which carries out a so-called collating process in which printouts obtained by distributed processing by a plurality of image recording apparatuses are arranged in page order, and performs book-binding as the need arises.
Further, information of booklets such as catalogs and product manuals recently circulating in the market and image information of booklets such as circulars for offices have been increasingly provided in color, and an increased number of such booklets have been composed of black-and-white images and color images. As is known, printing all the pages of the booklets using the color copying machine requires higher cost and longer time as compared with the black-and-white copying machine. For this reason, in recent years, a method has been generally employed in which original image data of a catalog or the like is separated into black-and-white pages and color pages, the black-and-white pages are printed by the black-and-white copying machine and the color pages are printed by the color copying machine, and then the pages printed by both copying machines are mixed into one unit by the above-mentioned post-processing apparatus (the collating and binding apparatus) or the like to produce a booklet.
The post-processing apparatus such as the collating and binding apparatus used in combination with the networked image recording system, however, requires bins in number corresponding to the number of pages of a booklet to be produced in order to discharge recording sheets, and therefore, there is the problem that the post-processing apparatus is large-sized.
To address this problem, a booklet producing method and a post-processing apparatus as described below have been proposed. For example, a server apparatus analyzes a print job of six pages consisting of three black-and-white pages and three color pages (refer to FIG. 57), and outputs such a print request that the color pages be printed by a color copying machine and the black-and-white pages by a black-and-white copying machine.
Each of the copying machines having received the print request discharges recording sheets such that m copies of recording sheets can be stacked in units of copy (refer to FIGS. 61A and 61B). The discharged recording sheets are transferred to trays of the post-processing apparatus on a tray-by-tray basis. On the other hand, the post-processing apparatus feeds the color pages and the black-and-white pages in page order from the respective trays in order to collate the recording sheets. The post-processing apparatus then binds the recording sheets as the need arises to complete a booklet (refer to FIG. 60).
The above described technique has been already known as a distributed processing type booklet producing system as disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 10-186953, for example. This distributed processing type booklet producing system is comprised of a server that distributes one job inputted from a client apparatus to a plurality of recording apparatuses for distributed processing, the plurality of recording apparatuses that record images on sheets based on the job according to an instruction from the server, and a post-processing apparatus that produces a booklet from the recording sheets outputted from the recording apparatuses. Further, the post-processing apparatus is comprised of a plurality of sheet feeding sections which are provided for the respective recording apparatus and in which the recording sheets outputted from the respective recording apparatuses are contained, and a control section that controls the operation of the plurality of sheet feeding sections according to information supplied from the server (the third prior art).
However, the above described first prior art has problems as described below.
To make it less complicated to combine printouts of a plurality of images into one document as mentioned above, a mixing control method has been proposed in which color image output sheets printed in advance are stacked in an inserter attached to a black-and-white image forming apparatus and the color image output sheets are refed. In this mixing control method, the color image output sheets outputted from a color image forming apparatus whose output speed is usually lower than that of the black-and-white image forming apparatus are once stored in an insert tray, and various information used for mixing the color image output sheets and the black-and-white image output sheets such as the job numbers of the print job, the sheet size, the number of copies to be printed, the stacked state of sheets in the inserter, and materials (the type of sheets; e.g. plain sheets and heavy sheets) is set using an operating section or the like, and according to the setting, information on color originals is downloaded from a server connected to a network or is read from a storage means of the image forming apparatus to form color images on sheets, so that the color image output sheets and the black-and-white image output sheets can be mixed.
However, when copying by the above conventional mixing control method, the user is still heavily burdened because copying errors can occur due to input errors made by the user or it is troublesome to make complicated settings. Particularly in the case where a plurality of black-and-white image forming apparatuses and a plurality of color image forming apparatuses are connected to each other via a network, a long downtime is caused by improper mixing of color image output sheets and black-and-white image output sheets resulting from inserter attachment errors.
Further, the above described second prior art has problems as described below. In the case where an image forming apparatus mixes color images and black-and-white images, the user is still heavily burdened because copying errors can occur due to input errors made by the user or it is troublesomeness to make complicated settings as is the case with the first prior art. Particularly in the case where a plurality of black-and-white image forming apparatuses and a plurality of color image forming apparatuses are connected to each other via a network, a large amount of miscopies and a long downtime can be caused by inserter attachment errors.
Further, in recent years, as there has been an increasing demand for small-lot and diversified color/black-and-white mixing jobs, it is inefficient to process the jobs using only one high-capacity stacker tray since a large number of large-sized stacker trays are required. Thus, it has been preferred that a plurality of smaller-sized stacker trays are allowed to be attached to a stacker (inserter) so that the stacker trays can be selectively used according to requirements from the user to improve the productivity of small-lot jobs.
In this case, managing and using the plurality of stacker trays selectively according to requirements from the user necessitates outputting sheets with images formed thereon to inserter of desired image forming apparatuses and to desired stacker trays without fail. This will increase the troublesomeness for the user, and raise the frequency of miscopy due to setting errors and attachment errors as compared with the case where only one stacker tray is used, and thus, the user is heavily burdened. Further, an increased number of complicated settings may be required since operations must be performed to reserve a stacker tray that is executing no job (i.e. a stacker tray which is not being used) so as to use the plurality of stacker trays appropriately according to requirements from the user. Further, it goes without saying that, in the case where a plurality of users share the image forming apparatus and the inserter, the troublesomeness and the downtime are increased due to setting errors and attachment errors.
Further, the above described third prior art has problems as described below.
Since the post-processing apparatus is comprised of the plurality of sheet feeding sections in which recording sheets outputted from the respective recording apparatuses are set, it is difficult for the user to recognize which bundle of sheets has not been set in the post-processing apparatus. Further, when producing a plurality of types of booklets, if bundles of sheets for a plurality of booklets are set in the trays of the post-processing apparatus, the user easily makes input errors since it is difficult for the user to determine which bundles of sheets belong to which booklets. It is also difficult for the user to determine whether all of bundles of sheets have been set or not. Further, there is the possibility that processing cannot be properly performed due to errors made by the user. Further, even if a certain recording apparatus has finished outputting, the user cannot recognize this and the outputted sheets are left as it is without being set in the post-processing apparatus by the user, and the processing speed may be lowered due to a delay in job progress in an off-line section even if the processing speed can be raised by distributed processing control.
Further, it is impossible to clearly recognize the contents of sheet feeding sections set in the post-processing apparatus. Further, the operability is not satisfactory since when the user sets the sheet feeding sections, on which recording sheets outputted from the recording apparatuses are stored, in the post-processing apparatus, he or sheet must carefully set the sheet feeding sections at respective positions suitable for the contents of the sheet feeding sections. Further, only a simple flow of work can be executed due to the possibility that sheets are lost due to operation errors made by the user.